Descaling device

ABSTRACT

The invention relates to a descaling device which can be operated in an optimal manner with respect to the efficiency, descaling quality, energy and water consumption and is readily available. The aim of the invention is achieved such that the spray nozzles ( 12 ), which are instrumental in descaling the steel material ( 2 ) in the descaling device ( 8 ), are designed as static nozzles and as dynamic or rotating nozzles. The static nozzles form, together with the spray bars, pairs of spray bars ( 13 ) and the dynamic or rotating nozzles form, together with spray units, rows of pairs of spray units ( 23 ).

The invention relates to a descaling device for hot steel material deformable along a production line into long and flat products, in accordance with the features of the preambles of claims 1, 16 and 17.

From DE 43 02 331 A1 is known a scale washer whose purpose is to descale in particular steel strips and thin slabs having reduced water and energy consumption over the entire strip or slab width deep into the pores. The object is met by utilizing a rotating nozzle head having several spray nozzles and preferably the two upper spray units arranged in the edge area of the rolling stock are offset relative to the two lower spray units arranged in the edge region of the rolling stock.

From DE 43 28 303 C2 is known a device for descaling hot rolling stock by applying a fluid which is under a high pressure, particularly water. The water emerges from at least one row of nozzles with several nozzle heads covering the rolling stock width, wherein each nozzle head is driven by a motor about an axis of rotation extending essentially perpendicularly of the surface of the rolling stock, and wherein each nozzle head has at least two nozzles arranged eccentrically relative to the axis of rotation. The nozzles of each nozzle head are arranged at different angles relative to the axis of rotation in such a way that the spray image of each nozzle during operation covers in relation to the axis of rotation a different radial area on the surface of the rolling stock to be descaled.

From EP 0 625 383 B1 is additionally known a manufacturing line for strips and/or sheet metal, in which, among others, as temperature restoring system is provided an induction furnace with at least one work frequency for heating the surface and the edges of the slabs, which is followed by a first descaling device and a tunnel furnace, and a second descaling device is provided between the tunnel furnace and the roll chain. The first descaling device is a low-speed descaling device with rotating nozzles, while the second descaling device is a high-speed descaling device with static nozzles.

Moreover, EP 1 718 424 B1 discloses a device for descaling hot rolling stock by means of water, in accordance with which at least one nozzle head row covering the rolling stock width is provided, and wherein each nozzle head is rotating and has several nozzles which are arranged near the circumference of the nozzle head in order to achieve spray images on the rolling stock which touch or overlap each other and in this way to remove the scale comparatively better.

Finally EP 1 077 095 B1 discloses a descaling device for a continuously cast metal strip which has particularly in the case of a defect significant advantages, inasmuch as the water catch channels arranged above the upper side of the metal strip are pivotable against the strip travel direction independently of the water spray nozzles assigned to them and are vertically adjustable and automatically yielding relative to the metal strip, and the spray beams of the strip upper side receiving the nozzle rows are freely pivotable by means of a lever arm and, thus, are arranged within limits so as to be vertically adjustable as well as automatically yielding.

The previously known descaling devices have for descaling the rolling stock either exclusively static nozzles or exclusively rotating nozzles. Accordingly, it is understandable that the previously known solutions make it only possible to influence a limited number of adjusting values, and it is consequently not possible to react to the product properties of the different long and flat steel products to be manufactured and to the process parameters and other target values.

The invention is based on the object of providing a descaling device which can be operated in an optimum manner with respect to its efficiency, the descaling quality, the energy and water consumption, and which has a high availability.

In accordance with the invention, this object is met with a descaling device with the features of claim 1, claim 16 and claim 17.

In accordance with the characterizing features of claim 1, the spray nozzles of the descaling device are constructed as static nozzles and as dynamic or rotating nozzles, and at least a predeterminable number of spray nozzles can be combined with each other with respect to their controlled or regulated quantities.

In another configuration of the invention, a certain number of static spray nozzles form a pair of spray beams together with a spray beam arranged above the steel material to be descaled and a spray beam arranged below the transport plane of steel material to be descaled, wherein the spray beam pair extends transversely of the transport plane. In this connection, several such spray beam pairs can be provided in the descaling device.

Moreover, in the descaling device, a certain number of dynamic or rotating spray nozzles are provided, which are arranged in several spray units arranged above spray units and in several spray units arranged below the transport plane, at least one spray unit row which extends transversely of the transport plane, and wherein always two essentially oppositely located spray unit rows form a spray unit row pair.

The at least one spray beam pair as well as the at least one spray unit row pair can according to the invention along its longitudinal extension form one or more spray zones to which water can be admitted as required. Individual spray zones can be switched on or off through suitable means, for example through adjusting valves, wherein at least one can be switched to the pressure source or can be switched off from the pressure source.

In a further development of the invention, different arrangement variations of individual spray beam pairs or individual spray unit row pairs can be present.

A first arrangement variation provides that, in the transport direction of the steel material, several spray beam pairs are arranged one after the other and always between a first spray beam pair and a second spray beam pair is arranged a device for squeezing or holding back the spray water impinging on the surface of the steel material.

A second arrangement variation provides that in the transport direction of the steel material at least one spray unit roll pair is arranged following a first and a second spray beam pair.

A third arrangement variation provides that between the first spray beam pair and the second spray beam pair at least one spray unit row pair is arranged.

A fourth arrangement variation provides that in transport direction of the steel material several spray unit row pairs are arranged one after the other and to the spray unit row pairs is assigned at least one spray beam pair.

A fifth arrangement variation provides that in transport direction of the steel material at least one spray unit row pair and after that at least one spray beam pair are arranged.

In accordance with another further development of the invention, always two spray beam modules are arranged offset relative to each other and opposite each other so as to form a spray beam module which is displaceably or exchangeably received in the housing of the descaling device transversely of the transport direction of the steel material.

Moreover, the respective spray unit rows are arranged on a travel rail present within the housing transversely of the transport plane and received in the manner of a module by the travel rail.

Furthermore, as already mentioned above, a device for squeezing off or holding back the spray water is arranged between always two spray beam pairs and/or between always two spray unit row pairs.

In accordance with the features of the preamble of claim 16, the object on which the invention is based is met by providing static nozzles as the spray nozzles which together with spray beams form at least a first and a second spray beam module, and that between both modules is arranged another device which serves for squeezing off or holding back the spray water impinging upon the surface of the steel material.

According to the features of the preamble of claim 17, the object of the invention is additionally solved by providing the spray nozzles as first static nozzles which together with spray beams form at least one spray beam module, and the spray nozzles are second dynamic or rotating nozzles which are formed in a nozzle head of a spray unit, wherein several of such spray units are arranged in the manner of a row above and below as well as transversely of the transport plane of the steel material and form a spray unit roll module, and that between the spray beam module and the spray unit row module is arranged another device which servers for squeezing off or holding back the spray water impinging upon the surface of the steel material to be descaled.

With respect to the arrangement of the descaling device within the production line, the latter can be positioned following a continuous casting machine and/or in a one-stand or multiple-stand hot rolling train configured as a production line, namely in front of at least one hot rolling stand.

Additional features of the invention result from the following description in which an embodiment of the invention will be explained in more detail.

In the drawings:

FIG. 1 shows the production line of the hot steel material which is deformable into a long and flat product, with the arrangement of the descaling device according to the invention following the continuous casting machine and in front of a two-high roll stand of a hot rolling train,

FIG. 2 shows the descaling device in a cross section with a first and a second spray beam pair, known per se, and

FIG. 3 shows the descaling device in a cross section with a spray beam pair and a spray unit row pair.

FIG. 1 shows a portion of a production line 1 which deforms a hot steel material 2 into a long and flat product.

The production line 1 includes a continuous casting machine 3, slab guide means 4, between which the steel material 2 is guided and transported into a horizontal plane for further processing. A first step of further processing may be, for example, that the steel material 2 passes a shear arrangement 5 synchronized with the casting speed in which the steel material is cut to sections of predetermined length. As is generally known, arranged in front of the shear arrangement 5 may be a straightening driver, not illustrated, which also is synchronized with the casting speed. Subsequently, for example, each section of the steel material 2 travels through a first descaling device 6 or 8 constructed in accordance with the invention. Following the first descaling device 6 or 8 may be provided a furnace 7 which raises the temperature of the steel material to the required temperature after the steel material 2 has cooled in the area near the surface thereof due to the spray water.

After the steel material 2 has passed the furnace 7, a second descaling device 6 or 8 constructed in accordance with the present invention may be arranged in front of a roll stand or a hot rolling train 9 with one or more stands.

With respect to the use of spray beams for descaling the steel material 2, FIG. 2 represents an embodiment of a known descaling device 6, inasmuch as it is known to construct spray nozzles 12, which are constructed as static nozzles, together with at least one spray beam 13.1 and 13.2 arranged above the transport plane 10 of the steel material 2 and at least one spray beam 13.1 and 13.2 arranged below the transport plane 10 of the steel material 2 to form a spray beam pair 13. This descaling device 6 comprises a housing 14 in which is formed the horizontally extending transport plane 10 in the rolling direction 15 for the steel material 2. The transport plane 10 is formed by roller table rollers 16 arranged within the housing 14 and over the longitudinal extension thereof and the rollers 17.1 of several devices 17 arranged in the housing 14 which rollers 17.1 are arranged with a parallel axis to the roller table rollers 16. The respective roller 17.1 of the device 17 serves together with another roller 17.2, which is arranged vertically and with a parallel axis above the roller 17.1, for squeezing or holding back the spray water which has impinged on the surface of the steel material 2.

As is well known, as also stated in DE 43 02 331 A1 and in EP 1 077 095 B1, a first device 17 is arranged on the inlet side and a second device 17 is arranged at the outlet side of the descaling device 6. Accordingly, such devices 17 are known, so that it is not necessary to discuss in more detail the constructive arrangement thereof.

The descaling device 6 includes additionally a first spray beam pair 13 and a second spray beam pair 20. The first spray beam pair 13 consists of the first spray beam 13.1 arranged below the transport plane 10 and the second spray beam 13.2 arranged above the transport plane 10. The first spray beam 13.1 is preferably constructed so as to be stationary, while the second spray beam 13.2 is preferably vertically adjustable. As known per se, each spray beam 13.1, 13.2 has assigned to it a spray water catch channel 18 or 19 arranged above the transport plane 10. While the spray water catch channel 18 assigned to the spray beam 13.1 is arranged preferably stationary, the spray water catch channel 19, assigned to the spray beam 13.2 is optionally arranged so as to be stationary or vertically adjustable. The spray beams 13.1, 13.2 form in the longitudinal extension thereof several spray zones, not illustrated, extending transversely over the longitudinal extension above the transport plane 10, wherein the spray zones can be switched on or off by suitable control means. This achieves an individual and targeted admission of spray water to the steel material 2 and simultaneously a reduction of the use of spray water and electrical energy for operating the spray water pressure source constructed, for example, as a conveyer pump is desired.

The second spray beam pair 20 arranged in the descaling device 6 is identical to the spray beam pair 13 with respect to configuration and arrangement. Also the assignment of the spray water catch channels 18, 19 is identical, so that further discussion in this connection are not necessary.

Advantageously, in the rolling direction 15 between the spray beam pair 13 and the spray beam pair 20 is arranged a device 17 for squeezing off or holding back the spray water, wherein the construction is identical to that of the device 17 arranged on the input side and the output side of the descaling device 6 and, in principle, corresponds to that disclosed in EP 1 077 095 B1.

The spray beam pair 13, 20 arranged in the descaling device 6 is additionally constructed as a spray beam module and is displaceably and exchangeably arranged in the housing 14 on suitable means transversely of the transport direction 11 of the steel material 2.

Finally, the housing 14 of the descaling device 6 is covered from above by a hood 21. The purpose of such a hood 21 is sufficiently described in EP1 077 095 B1, so that further comments concerning the hood are not necessary.

FIG. 3 shows a descaling device 8 which differs from the devices known from the prior art and described in FIG. 2. The difference resides in that, for descaling the steel material 2, spray nozzles 12 are used which are constructed as static nozzles and which form together with at least one spray beam 13.1, 13.2 arranged below the transport plane 10 and at least one spray beam 13.1, 13.2 arranged above the transport plane 10 so as to form a spray beam pair 13 or a spray beam module, and spray nozzles are used which are constructed as dynamic or rotating spray nozzles and which are arranged in several spray units 22 arranged above and below the transport plane 10. The spray units 22 are constructed so as to form always at least one spray unit row 22.1, 22.2 which are located offset opposite each other and transversely above and below the transport plane 10 of the steel material 2. In this manner, two such spray unit rows, 22.1, 22.2 form a spray unit row pair 23. Each spray beam of the spray beam pair 13 and each spray unit row of the spray unit row pairs 23 can be divided over its longitudinal extension in several spray zones in order to spray water as needed and in a targeted manner on the surface of the steel material 2 to be descaled. For this purpose, suitable means, not shown, are provided by means of which the spray beam pair 13 and the spray unit row pair 23 as well as the spray zones of the pairs 13, 23 can be switched on and off as needed to a pressure source, not illustrated. In order to be able to react to the different conditions and requirements to be able to descale with suitable quality additionally within the housing 14 different arrangement variations of the at least one spray beam pair 13 and of the at least one spray unit row pair 23 are conceivable.

FIG. 3 shows one of the embodiments.

Following the spray beam pair 13 with the corresponding spray water catch channel 18, 19 is in this case in the transport direction 11 or in rolling direction 15 a spray unit row pair 23 with the corresponding spray water catch box 24, 25. Between the spray beam pair 13 and the spray unit row pair 23 is a device 17 for squeezing off or holding back the spray water, as already described in connection with FIG. 2. The spray unit rows 22.1, 22.2 and/or the individual spray units 22 are also in this case constructed in the manner of a module, so that in case of damage the modules can be replaced without significant problems. The spray unit row 22.1 arranged below the transport plane 10 can, for example, be received by a travel rail 26 arranged within the housing 14, or the spray unit row 22.2 arranged above the transport plane 10 can be arranged so as to be moveable above the transport plane 10 at the hood 21.

The use of two spray nozzles 12 of different construction and with spray nozzles 12 with different effects for descaling in a descaling device 8, i.e. static and rotating spray nozzles, results in an advantageous manner in a surface quality of the steel material 2 which meets highest requirements and which leads to lowering of the energy and water consumption. In this way, in the case of temperature-critical products, for example, during thin slab rolling or during austenitic rolling, descaling takes place exclusively by means of the dynamic or rotating spray nozzles, i.e. by means of the at least one spray unit row pair 23, while during highest requirements of the surface quality of the steel product 2 the spray unit row pair 23 as well as the spray beam pairs 13 are switched on.

The use of differently acting spray nozzles 12 leads in an advantageous manner to the result that, with the same manner of operating the spray unit row pair 23 and of the spray beam pair 13, breaking of the scale can be effected with the first spray beam pair 13 as seen in the transport direction 10 and the cleaning of the surface of the steel material 2 from the broken scale can take place with the second spray unit row pair 23.

LIST OF REFERENCE NUMERALS

-   1. Production line -   2. Steel material -   3. Casting machine -   4. Slab guide means -   5. Shear arrangement -   6. Descaling device -   7. Furnace -   8. Descaling device -   9. Rolling stand -   10. Transport plane -   11. Transport direction -   12. Spray nozzle -   13. Spray beam pair -   13.1 Spray beam -   13.2 Spray beam -   14 Housing -   15 Rolling direction -   16 Roll -   17 Device -   17.1 Roll -   17.2 Roll -   18 Spray water catch channel -   18 Spray water catch channel -   20 Spray beam pair -   21 Hood -   22 Spray unit -   22.1 Spray unit row -   22.2 Spray unit row -   23 Spray unit row pair -   24 Spray water catch box -   25 Spray water catch box -   26 Rail 

1-18. (canceled)
 19. A descaling device for a hot steel material deformable along the production line into long and flat products, comprising a housing, a transport plane for the steel material; spray nozzles arranged vertically above and/or below the transport plane and directed to a surface of the steel material, from which spray nozzles water emerges under high pressure for descaling the surface of the steel material in a controlled and/or regulated manner; a spray beam arranged below the transport line and a spray beam arranged above the transport line as a spray beam pair or a spray beam module, the spray nozzles being arranged on the spray beams and being constructed as static nozzles and as dynamic or rotating spray nozzles, the spray nozzles being combinable with each other with respect to the controlled and/or regulated emission of spray water.
 20. The descaling device according to claim 19, wherein the spray beams are arranged transversely of the transport plane of the steel material and, together with the static spray nozzles form the spray beam pair, the dynamic or rotating spray nozzles being arranged in at least one spray unit arranged above the transport plane and at least one spray unit arranged below the transport plane, the respective spray units arranged above and below the transport plane being mounted to form at least one spray unit row and extend transversely above and below the transport plane of the steel material, wherein the two spray unit rows are arranged so as to be offset opposite each other and form a spray unit row pair.
 21. The descaling device according to claim 20, wherein at least one spray beam pair and at least one spray unit row pair form several spray zones in a longitudinal extension.
 22. The descaling device according to claim 21, and further comprising means for individually switching the spray zones on and off.
 23. The descaling device according to claim 21, wherein several spray beam pairs are arranged behind one another in a transport direction of the steel material.
 24. The descaling device according to claim 20, wherein at least one spray unit row pair is arranged following a first and a second spray beam pair in a transport direction of the steel material.
 25. The descaling device according to claim 20, wherein at least one spray unit row pair is arranged between a first spray beam pair and a second spray beam pair.
 26. The descaling device according to claim 20, wherein several spray unit row pairs are arranged behind one another in a transport direction of the steel material, at least one spray beam pair being assigned to the spray unit row pairs.
 27. The descaling device according to claim 20, wherein at least unit row pair is arranged in a transport direction of the steel material and thereafter is arranged at least one spray beam pair.
 28. The descaling device according to claim 20, wherein two spray beams are always arranged opposite each other and offset relative to each other to form the spray beam module.
 29. The descaling device according to claim 28, wherein each spray beam module is arranged in the housing so as to be slideable transversely of a transport direction of the steel material.
 30. The descaling device according to claim 28, wherein the spray beam modules are arranged so as to be replaceable.
 31. The descaling device according to claim 30, and further comprising a travel rail arranged in the housing, the respective spray unit rows being arranged on and received by the travel rail as a module.
 32. The descaling device according to claim 28, and further comprising a first device and a second device for squeezing off or holding back the spray water, each spray beam module being arranged between the first device and the second device.
 33. The descaling device according to claim 31, and further comprising a first device and a second device for squeezing off or holding back the spray water, each spray unit row pair being arranged between the first device and the second device.
 34. A descaling device for hot steel material deformable along a production line into long and flat products, comprising: a housing, a transport plane for the steel material within the descaling device; spray nozzles arranged vertically above and below the transport plane directed onto a surface of the steel material, from which spray nozzles water emerges under high pressure for descaling the surface of the steel material in a controlled or regulated manner; a device arranged on an input side and an output side of the housing for squeezing off or holding back the spray water impinging upon the surface of the steel material; spray beams, the spray nozzles being static nozzles which together with the spray beams form at least one first and second spray beam module; and another device for squeezing off or holding back the spray water impinging upon the surface of the steel material, the another device being arranged between the first and the second spray beam modules.
 35. A descaling device for hot steel material deformable along a product line into long and flat products, comprising: a housing, a transport plane for the steel material within the descaling device; spray nozzles arranged vertically above and below the transport plane directed onto a surface of the steel material, from which spray nozzles water emerges under high pressure for descaling the surface of the steel material in a controlled or regulated manner; a device arranged on an input side and an output side of the housing for squeezing off or holding back the spray water impinging upon the surface of the steel material; a spray beam, the spray nozzles including static nozzles which together with spray beam form at least one spray beam module, and the spray nozzles including dynamic or rotating nozzles which are arranged in a spray head of a spray unit, wherein several such spray units are arranged as a spray unit row above and below as well as transversely of the transport plane of the steel material and form a spray unit row module; and another device which for squeezing off or holding back the spray water impinging upon the surface of the steel material, the another device being arranged between the spray beam module and the spray unit row module.
 36. The descaling device according to claim 19, wherein the descaling device is arranged in a one-stand or multiple-stand hot rolling train formed as a production line, either following a continuous casting machine or in front of at least one hot rolling stand. 